Fig. 5: Tumor-suppressing capability of PANP-RAWs in vitro and in vivo.

A Schematic representation of the workflow to collect supernatant of RAW264.7 cells carrying different types of nanoparticles (RAW-NPs) to treat MDA-MB-231 cells. B Cell viability analysis of MDA-MB-231 cells in 0, 12, 24, and 48 h after treatment with supernatants of RAW-NPs. C Representative ultrasound images of the central part of the tumor tissue of MDA-MB-231 tumor-bearing mice, 10, 20, 30, and 40 min after tail resting injection of PANP-RAW (blue arrows point to the area of greatest PANP enrichment. D Quantitative analysis of echo signal intensities in C. E MDA-MB-231 tumor-bearing mice, Empty-NP-RAW, PTX-NP-RAW, miR-NP-RAW, PANP, and PANP-RAW, were injected tail-resting every three days, and after homing tumor tissues, tumor sites were ultrasonicated, and tumor growth curves of mice were treated for 2 consecutive weeks (n = 5 mice per group). F Tumor growth curves of the breast tumor-burden mice injected with different types of RAW-NPs through tail-vein, followed by an ultrasonic burst to release drugs 24 h after each injection. Empty nanoparticles in RAW264.7 were used as a control (n = 6 in each group). G Quantitative analysis of tumor weight in E. H, I Quantitative analysis of miR-221 (H) and p27 (I) in the tumors of different experimental groups. Data are presented as the mean ± SEM (n = 3 in B, D, H and I, n = 6 in E and G). *P < 0.05, **P < 0.01.